Stethoscope



J. D. POLLARD.

STE-THOSCOPE.

APPLICATION FILED NOV. 7. 1917.

1,329,430. Patented Feb. 3,

W i Q Ill/Mamie}.-

. TIE/Z217. Pollard, I

J OHN D. POLLARD, OF CHICAGO, ILLINOIS.-

STETI-IOSCOPE.

Specification of Letters Patent.

Patented Feb. 3, 1920.

Application filed November 7, 1917. Serial No. 200,701.

To all whom it may concern Be it known that I, JOHN D. PoLLARo, a citizen of the United States, and a resident of the city of Chicago, county of Cook, and State of Illinois, have invented certain new and useful Improvements in Stethoscopes, of which the following is a specification.

My invention relates to improvements in stethoscopes; and has for its object the provision of an improved construction of this character, which is simple and efficient in use, and which may be adjusted in sensitiveness and the sounding diaphragm readily renewed when desired.

The invention consists in the combinations and arrangements of parts hereinafter described and claimed.

The invention will be best understood by reference to the accompanying drawing forming a part of this specification, and in which,

Figure l is a side view of a portion of a stethoscope embodying the invention,

Fig. 2, an enlarged detail section taken through the sounding chamber of the stethoscope, and

Fig. 3, an end View of said sounding chamber.

The preferred form of construction as illustrated in the drawing, comprises a substantially cup-shaped sounding chamber 4, having an open mouth and equipped with the usual ear tubes 5 in open communication therewith, and leading to the usual ear pieces not shown. A clamping band is arranged about the sound chamber 4 to slide freely on the walls thereof, said clamping band consisting of outer and inner cooperating clamping ring sections 6 and 7, the ring section 7 fitting within the ring section 6 as indicated. A plurality of clamping links or rods 8 are pivotally connected with the outer ring section 6 andare arranged to swing toward and away from the outer walls of sound chamber 4 and through notches in lugs 9 on said sound chamber. Each of the links 8 is equipped with a compression spring 10, arranged to be imprisoned between the corresponding lug 9 and the inner edges of the ring sections 6 and 7 and a clamping nut 11 is threaded on the free end of each of the links 8 and adapted to rest against the corresponding lug 9. The diaphragm for the sound chamber 4 is in the form of an elastic sheet of rubber 12, stretched over the mouth of said sound chamber, having its edges clamped between the rings 6 and 7 as indicated.

By this arrangement, it will be observed, that the rubber sheet forming the sound diaphragm may be readily and uniformly stretched across the mouth of the sound chamber and that the tension therein may be varied, as desired, the greater the tension the more sensitive the diaphragm and sound chamber and vice versa. Also the diaphragm may be readily renewed in case of puncture or in case the rubber loses its elasticity and consequently its sensitiveness.

While I have illustrated and described the preferred form of construction for carrying my invention into effect, this is capable of variation and modification without departing from the spirit of the invention. I, therefore, do not wish to be limited to the precise details of construction set forth, but desire to avail myself of such variations and modifications as come within the scope of the appended claims.

Having described my invention what I claim as new and desire to secure by Letters Patent is: i

1. A stethoscope comprising an openmouthed sounding chamber; a diaphragm stretched over the mouth of said chamber; a band surrounding said chamber and sliding freely thereon, said band securing the edges of said diaphragm; and means for adjusting said band with reference to the mouth of said chamber.

2. A stethoscope comprising an openmouthed sounding chamber; a diaphragm securing band surrounding said chamber and sliding freely thereon; an elastic extensible diaphragm stretched over the mouth of said chamber and having its edges secured to said band; and means for adjusting said band with reference to the mouth of said chamber, substantially as described.

3. A stethoscope comprising an open mouthed sounding chamber; a diaphragm securing band surrounding said chamber and sliding freely thereon, said band consisting of two separable ring sections, one fitting within the other and adapted to clamp the edges of a rubber sheet stretched over the mouth of said sounding chamber, the edges of said diaphragm being clamped between said ring sections; clamping links pivoted to the outer ring section to swing toward and awayfrom the sides of said sounding chamber; lugs on the sides of said sounding chamber, notched to receive said name to this specification in the presence of clampinig links;d connilipreossion sprindgs imtwo subscribing Witnesses.

risone on sai 1i s etween sai outer i ing section and said lugs; and clamping JOHN POLLARD' 5 nuts threaded on said links and bearing Witnesses:

against said lugs, substantially as described. JOSHUA R. H. Po'r'rs,

In testimony whereof I have signed my MILDRED E. ANDERSON. 

